There have been a total of 5 types of wheel nuts used across the Series Land Rover range. Early wheel nuts upto Series IIA suffix B were of the symmetrical type with rounded faces at each end (LHS photo part number 217361). So they could be fitted either way around. These nuts have BSF threads and are 59/64inch AF spanner size (or number 23 socket). The nuts were 1inch long upto 1968-69 and then shorter versions 11/16inch long were used. These shorter nuts were also reversable but were soon replaced with a single taper nut with BSF thread and 3/4inch long, requiring a 1 1/16inch AF spanner. There was a problem with these nuts originally as they could damage the wheel rim when fully tightened , so they were replaced in 1969 with a 9/16inch long BSF threaded nut (part number 576103). These use a 27 socket and appear the same as the series III nuts introduced later but they fit the SII screw-in studs. Then in 1971, for the Series III, a metric wheel nut to fit the wider studs (part number 90577473, RHS photo) was introduced requiring a number 27 socket.

As with any nut tightening, torque is important, but this is particularly so with the double tapered nuts. The associated studs for these nuts are screwed into the hub assembly and the inner edge of the stud is simply crimped to hold it secure. It requires very little extra torque to break this stud free, given the age that these hubs now are. Being cast iron it is not easy to make a weld repair to hold these studs secure again. Once a stud breaks free it can be only a matter of a few hundred yards of road travel before the other nuts work loose (trust me on this!).

Wheel hubs of the screw-in stud type (part number 576475) seem to be no longer available and the Series III hub is recommended as a replacement (part number 576844), with its pressed-in splined studs. The correct torque for wheel nuts on the splined studs is 75-85lb ft. The studs on this hub may not fit through the holes in the earlier brake drum though. It is possible in some cases to drill out the brake drum holes a little, rather than obtain a matching brake drum.
In general, for tightening wheel nuts, it is NOT necessary to use extension bars to tighten them or stand on the standard wheel brace unless your muscles are in worse condition than your vehicle!